test: improve worker choice strategies testing

[poolifier.git] / tests / pools / selection-strategies / selection-strategies.test.js

diff --git a/tests/pools/selection-strategies/selection-strategies.test.js b/tests/pools/selection-strategies/selection-strategies.test.js
index e8d9d66b751e305b79ce2e5147eedb3eb6bcb48a..19ac5ea3a9a930c67996efd31fb5a683aa856685 100644 (file)
--- a/tests/pools/selection-strategies/selection-strategies.test.js
+++ b/tests/pools/selection-strategies/selection-strategies.test.js
@@ -5,6 +5,7 @@ const {
   FixedThreadPool,
   FixedClusterPool
 } = require('../../../lib')
+const { CircularArray } = require('../../../lib/circular-array')
 
 describe('Selection strategies test suite', () => {
   const min = 0
@@ -12,8 +13,8 @@ describe('Selection strategies test suite', () => {
 
   it('Verify that WorkerChoiceStrategies enumeration provides string values', () => {
     expect(WorkerChoiceStrategies.ROUND_ROBIN).toBe('ROUND_ROBIN')
-    expect(WorkerChoiceStrategies.LESS_USED).toBe('LESS_USED')
-    expect(WorkerChoiceStrategies.LESS_BUSY).toBe('LESS_BUSY')
+    expect(WorkerChoiceStrategies.LEAST_USED).toBe('LEAST_USED')
+    expect(WorkerChoiceStrategies.LEAST_BUSY).toBe('LEAST_BUSY')
     expect(WorkerChoiceStrategies.FAIR_SHARE).toBe('FAIR_SHARE')
     expect(WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN).toBe(
       'WEIGHTED_ROUND_ROBIN'
@@ -80,12 +81,12 @@ describe('Selection strategies test suite', () => {
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).workersVirtualTaskTimestamp
+          ).workersVirtualTaskEndTimestamp
         ).toBeInstanceOf(Array)
         expect(
           pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
             workerChoiceStrategy
-          ).workersVirtualTaskTimestamp.length
+          ).workersVirtualTaskEndTimestamp.length
         ).toBe(0)
       } else if (
         workerChoiceStrategy === WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
@@ -118,14 +119,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: false,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     await pool.destroy()
     pool = new DynamicThreadPool(
       min,
@@ -134,14 +136,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: false,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -153,12 +156,29 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.ROUND_ROBIN }
     )
     // TODO: Create a better test to cover `RoundRobinWorkerChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: 0,
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -171,12 +191,29 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.ROUND_ROBIN }
     )
     // TODO: Create a better test to cover `RoundRobinWorkerChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: 0,
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -190,7 +227,7 @@ describe('Selection strategies test suite', () => {
     )
     let results = new Set()
     for (let i = 0; i < max; i++) {
-      results.add(pool.chooseWorkerNode()[1].worker.id)
+      results.add(pool.workerNodes[pool.chooseWorkerNode()].worker.id)
     }
     expect(results.size).toBe(max)
     await pool.destroy()
@@ -201,7 +238,7 @@ describe('Selection strategies test suite', () => {
     )
     results = new Set()
     for (let i = 0; i < max; i++) {
-      results.add(pool.chooseWorkerNode()[1].worker.threadId)
+      results.add(pool.workerNodes[pool.chooseWorkerNode()].worker.threadId)
     }
     expect(results.size).toBe(max)
     await pool.destroy()
@@ -247,22 +284,23 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify LESS_USED strategy default tasks usage statistics requirements', async () => {
-    const workerChoiceStrategy = WorkerChoiceStrategies.LESS_USED
+  it('Verify LEAST_USED strategy default tasks usage statistics requirements', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
     let pool = new FixedThreadPool(
       max,
       './tests/worker-files/thread/testWorker.js',
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: false,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     await pool.destroy()
     pool = new DynamicThreadPool(
       min,
@@ -271,69 +309,105 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: false,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LESS_USED strategy can be run in a fixed pool', async () => {
+  it('Verify LEAST_USED strategy can be run in a fixed pool', async () => {
     const pool = new FixedThreadPool(
       max,
       './tests/worker-files/thread/testWorker.js',
-      { workerChoiceStrategy: WorkerChoiceStrategies.LESS_USED }
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_USED }
     )
-    // TODO: Create a better test to cover `LessUsedWorkerChoiceStrategy#choose`
-    const promises = []
+    // TODO: Create a better test to cover `LeastUsedWorkerChoiceStrategy#choose`
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: 0,
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LESS_USED strategy can be run in a dynamic pool', async () => {
+  it('Verify LEAST_USED strategy can be run in a dynamic pool', async () => {
     const pool = new DynamicThreadPool(
       min,
       max,
       './tests/worker-files/thread/testWorker.js',
-      { workerChoiceStrategy: WorkerChoiceStrategies.LESS_USED }
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_USED }
     )
-    // TODO: Create a better test to cover `LessUsedWorkerChoiceStrategy#choose`
-    const promises = []
+    // TODO: Create a better test to cover `LeastUsedWorkerChoiceStrategy#choose`
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: 0,
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LESS_BUSY strategy default tasks usage statistics requirements', async () => {
-    const workerChoiceStrategy = WorkerChoiceStrategies.LESS_BUSY
+  it('Verify LEAST_BUSY strategy default tasks usage statistics requirements', async () => {
+    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
     let pool = new FixedThreadPool(
       max,
       './tests/worker-files/thread/testWorker.js',
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     await pool.destroy()
     pool = new DynamicThreadPool(
       min,
@@ -342,49 +416,86 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(false)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: false,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LESS_BUSY strategy can be run in a fixed pool', async () => {
+  it('Verify LEAST_BUSY strategy can be run in a fixed pool', async () => {
     const pool = new FixedThreadPool(
       max,
       './tests/worker-files/thread/testWorker.js',
-      { workerChoiceStrategy: WorkerChoiceStrategies.LESS_BUSY }
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_BUSY }
     )
-    // TODO: Create a better test to cover `LessBusyWorkerChoiceStrategy#choose`
-    const promises = []
+    // TODO: Create a better test to cover `LeastBusyWorkerChoiceStrategy#choose`
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify LESS_BUSY strategy can be run in a dynamic pool', async () => {
+  it('Verify LEAST_BUSY strategy can be run in a dynamic pool', async () => {
     const pool = new DynamicThreadPool(
       min,
       max,
       './tests/worker-files/thread/testWorker.js',
-      { workerChoiceStrategy: WorkerChoiceStrategies.LESS_BUSY }
+      { workerChoiceStrategy: WorkerChoiceStrategies.LEAST_BUSY }
     )
-    // TODO: Create a better test to cover `LessBusyWorkerChoiceStrategy#choose`
-    const promises = []
+    // TODO: Create a better test to cover `LeastBusyWorkerChoiceStrategy#choose`
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
+    for (const workerNode of pool.workerNodes) {
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+    }
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -397,14 +508,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: true,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     await pool.destroy()
     pool = new DynamicThreadPool(
       min,
@@ -413,14 +525,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: true,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -432,22 +545,35 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.FAIR_SHARE }
     )
     // TODO: Create a better test to cover `FairShareChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThanOrEqual(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBe(0)
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: expect.any(Number),
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThan(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(pool.workerNodes.length)
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -461,28 +587,41 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.FAIR_SHARE }
     )
     // TODO: Create a better test to cover `FairShareChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThanOrEqual(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBe(0)
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: expect.any(Number),
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThan(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(pool.workerNodes.length)
     // We need to clean up the resources after our test
     await pool.destroy()
   })
 
-  it('Verify FAIR_SHARE strategy can be run in a dynamic pool with median run time statistic', async () => {
+  it('Verify FAIR_SHARE strategy can be run in a dynamic pool with median runtime statistic', async () => {
     const pool = new DynamicThreadPool(
       min,
       max,
@@ -495,22 +634,35 @@ describe('Selection strategies test suite', () => {
       }
     )
     // TODO: Create a better test to cover `FairShareChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.avgRunTime).toBe(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBeGreaterThanOrEqual(0)
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: expect.any(Number),
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.medRunTime).toBeGreaterThan(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         pool.workerChoiceStrategyContext.workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(pool.workerNodes.length)
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -525,31 +677,31 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp
+      ).workersVirtualTaskEndTimestamp
     ).toBeInstanceOf(Array)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(0)
     pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
       workerChoiceStrategy
-    ).workersVirtualTaskTimestamp[0] = 0
+    ).workersVirtualTaskEndTimestamp[0] = performance.now()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(1)
     pool.setWorkerChoiceStrategy(workerChoiceStrategy)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp
+      ).workersVirtualTaskEndTimestamp
     ).toBeInstanceOf(Array)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(0)
     await pool.destroy()
     pool = new DynamicThreadPool(
@@ -560,31 +712,31 @@ describe('Selection strategies test suite', () => {
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp
+      ).workersVirtualTaskEndTimestamp
     ).toBeInstanceOf(Array)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(0)
     pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
       workerChoiceStrategy
-    ).workersVirtualTaskTimestamp[0] = 0
+    ).workersVirtualTaskEndTimestamp[0] = performance.now()
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(1)
     pool.setWorkerChoiceStrategy(workerChoiceStrategy)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp
+      ).workersVirtualTaskEndTimestamp
     ).toBeInstanceOf(Array)
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
         workerChoiceStrategy
-      ).workersVirtualTaskTimestamp.length
+      ).workersVirtualTaskEndTimestamp.length
     ).toBe(0)
     // We need to clean up the resources after our test
     await pool.destroy()
@@ -598,14 +750,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: true,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     await pool.destroy()
     pool = new DynamicThreadPool(
       min,
@@ -614,14 +767,15 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy }
     )
     expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().runTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime
-    ).toBe(true)
-    expect(
-      pool.workerChoiceStrategyContext.getRequiredStatistics().medRunTime
-    ).toBe(false)
+      pool.workerChoiceStrategyContext.getRequiredStatistics()
+    ).toStrictEqual({
+      runTime: true,
+      avgRunTime: true,
+      medRunTime: false,
+      waitTime: false,
+      avgWaitTime: false,
+      medWaitTime: false
+    })
     // We need to clean up the resources after our test
     await pool.destroy()
   })
@@ -633,17 +787,30 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN }
     )
     // TODO: Create a better test to cover `WeightedRoundRobinWorkerChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: expect.any(Number),
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThanOrEqual(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThanOrEqual(0)
       expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThanOrEqual(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBe(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -667,17 +834,30 @@ describe('Selection strategies test suite', () => {
       { workerChoiceStrategy: WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN }
     )
     // TODO: Create a better test to cover `WeightedRoundRobinWorkerChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThanOrEqual(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBe(0)
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: expect.any(Number),
+        medRunTime: 0,
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.avgRunTime).toBeGreaterThan(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(
@@ -693,7 +873,7 @@ describe('Selection strategies test suite', () => {
     await pool.destroy()
   })
 
-  it('Verify WEIGHTED_ROUND_ROBIN strategy can be run in a dynamic pool with median run time statistic', async () => {
+  it('Verify WEIGHTED_ROUND_ROBIN strategy can be run in a dynamic pool with median runtime statistic', async () => {
     const pool = new DynamicThreadPool(
       min,
       max,
@@ -706,17 +886,30 @@ describe('Selection strategies test suite', () => {
       }
     )
     // TODO: Create a better test to cover `WeightedRoundRobinWorkerChoiceStrategy#choose`
-    const promises = []
+    const promises = new Set()
     const maxMultiplier = 2
     for (let i = 0; i < max * maxMultiplier; i++) {
-      promises.push(pool.execute())
+      promises.add(pool.execute())
     }
     await Promise.all(promises)
     for (const workerNode of pool.workerNodes) {
-      expect(workerNode.tasksUsage.avgRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.avgRunTime).toBe(0)
-      expect(workerNode.tasksUsage.medRunTime).toBeDefined()
-      expect(workerNode.tasksUsage.medRunTime).toBeGreaterThanOrEqual(0)
+      expect(workerNode.tasksUsage).toStrictEqual({
+        run: expect.any(Number),
+        running: 0,
+        runTime: expect.any(Number),
+        runTimeHistory: expect.any(CircularArray),
+        avgRunTime: 0,
+        medRunTime: expect.any(Number),
+        waitTime: 0,
+        waitTimeHistory: expect.any(CircularArray),
+        avgWaitTime: 0,
+        medWaitTime: 0,
+        error: 0
+      })
+      expect(workerNode.tasksUsage.run).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.run).toBeLessThanOrEqual(max * maxMultiplier)
+      expect(workerNode.tasksUsage.runTime).toBeGreaterThan(0)
+      expect(workerNode.tasksUsage.medRunTime).toBeGreaterThan(0)
     }
     expect(
       pool.workerChoiceStrategyContext.workerChoiceStrategies.get(